MMP1 and melanoma: Mechanistic studies have shown that melatonin enhanced vemurafenib efficacy in the inhibition of cell migration and invasion of melanoma cells; and decreased the expression of matrix metalloproteinase 1 (MMP-1), vimentin, and β-catenin; and upregulated the expression of E-cadherin, indicating that this combination inhibits epithelial-to-mesenchymal transition (EMT) [11].